code: def df_mapplot():
      df_mapplot = pd.read_csv(
          os.path.join(
              TEST_SETS_DIRECTORY,
              "populated places",
              "populated_places.csv",
          )
      )
      df_mapplot["size"] = df_mapplot["pop_max"] / 1000000
  
      return df_mapplot
  
imports: import os
  import numpy
  import pandas
  import pytest
  import pandas_bokeh
label_desc: Use image node_id 7 for calling a global function with example usage: df_mapplot() and returns: df_mapplot